Intel Atom May Power 'Green' Servers

Though slow compared with state-of-the-art multicore server CPUs, Atom processors draw less electricity to run and cool them -- as little as one-twentieth of the energy required by conventional server processors, according to Jim Larus, director of software architecture at Microsoft Research, speaking at the company's TechFest last week (YouTube video downloadable here).

"They're not as powerful, so you may require many more of these servers in the data center, but since each one consumes less energy, the data center as a whole can be more efficient and get more work done for the same amount of energy," he said.

In the video, Larus shows a prototype server rack holding 50 Atom systems, which, because of the low heat generated by the Atom, doesn't require a powerful fan for cooling the rack, though there are still fans for each individual Atom CPU. These could be used in Microsoft's massive data centers alongside conventional servers and servers deployed in shipping containers.

Because they were designed for laptops and netbooks, Atom CPUs can be quickly put into sleep/hibernate states and then quickly woken up, said Dave Ohara, a consultant who runs the Green Data Center blog, unlike desktop and server CPUs.

According to Microsoft, today's average server sits idle 75% of the time. Putting idle Atom servers to sleep could cut their energy usage by another 90%, says Microsoft, to about 3 to 4 watts for the entire system.

Judging by the US$300 to $400 cost of Atom-based netbooks, Ohara said that racks of Atom-based server blades could be made for even less.

"Intel hates this, because they want to sell you more expensive multicore Xeon processors," Ohara said. "But sometimes small is more beautiful."

SingleHop Inc., a Chicago hosting provider, began leasing dual-core Atom servers to customers in October. According to a post at SingleHop's blog, the Atom server is "faster than a Pentium 4" and uses 75% less power.

While Microsoft is looking at Atom servers for its own massive data centers, Ohara says Atom servers would be potentially more useful for small to medium-size businesses that prefer retaining security and control of their own servers over storing their data and using the applications of a cloud-based service such as Salesforce.com or Amazon.com Inc.'s S3.

"If you have a low-load situation, like most SMB servers are, an Atom can work fine," he said.